The field of the invention relates to the problem of gas leaks. In particular, the invention pertains to a method and system for detection and location of leaks from various pressurized components.
Many industrial and domestic machines use or convey pressurized gases or liquids. Leaks from these machines may be costly to consumers as well as manufacturers, and moreover, depending on the composition of the gas or liquid, the leaks could be harmful to the environment.
Heretofore, several methods of leak testing have been employed. Methods such as bubble visualization, sniffing, pressure decay, evacuating the part to create a vacuum and surrounding the part with a gas and checking for any intrusion of the gas into the part, pressurization/immersion, pressurization/soaping, and pressurization/ammonia sensitive painting are some of the various techniques that have been used with varying degrees of success. Most of these techniques and their drawbacks are described in U.S. Pat. No. 5,161,408 to McRae, et al. The McRae et al. patent discusses a photo-acoustic leak detection system and method that employs a single microphone and narrowband signal processing. Photo-acoustics is the excitation of acoustic waves by unsteady heat addition from a light source. This phenomena was discovered more than a century ago. Photo-acoustics has been used primarily for spectroscopy and most measurements have been made in closed acoustically resonant cells.
Despite the need for a method and system for photoacoustic detection and localization of leaks, especially small leaks, without the necessity of synchronization and with the use of broadband matched-field signal processing, none was known. Thus, there existed the need for a method and system for photoacoustic detection and localization of leaks without synchronization and with the use of broadband matched-field signal processing.
The disclosed method and system of this invention is applicable to a wide range of leak problems, including but not limited to consumer or industrial products such as automobile components, refrigerators, air conditioners and electrical equipment that includes parts that contain liquids or pressurized gases.
The present method and system does not require synchronization, and uses broadband matched-field signal processing across all signal frequencies. The method and system are described below.